Electronic Control Module (ECM) Electrical Connectors

Connector - Pre Diagnosis Checks - Generic

Note the following connector related information before you start any diagnosis:

notice
A major cause of hidden electrical faults can be traced to faulty electrical connectors.

For example:

  • Dirty/corroded terminals

  • Damp terminals

  • Broken or bent cable pins within multiplugs.

For example, the ABS electronic control module (ABS modulator/ECM) relies on the supply of accurate information to enable it to monitor and control the brake system. One dirty terminal will cause an excessive voltage drop resulting in an incorrect signal to the ECM.

If, when carrying out fault diagnosis, a fault appears to clear by simply disconnecting and reconnecting an electrical connector, examine each disconnected connector for the following.

Before Disconnection:

  • If testing with a voltmeter, the voltage across a connector battery supply and ground pins should be virtually battery volts with a small deviation allowable for usual voltage drop within wiring circuits. If there is a noticeable change, suspect faulty/dirty connections. Refer to the circuit diagram within this Service Manual for pin numbers.

When Disconnecting a Connector:

  • Check for a security device that must be released before the connector can be separated. For example: barb, hook and eye and so on.

When Inspecting a Connector:

  • Check that the individual pins have not been bent.

  • Check for dampness/dirt/corrosion.

  • Check cables for security.

  • Check cable pin joints for damage.

When Connecting a Connector:

  • Make sure there is no contamination around the connector/seal.

  • Push together squarely to make sure that the terminals are not bent or incorrectly located.

  • Push the two halves together positively.